I recently received some Domaine Ponsot in my store and was struggling to determine the state of the thermal indicator on the bottle, finding reference photos online was difficult.
I wanted to share the reference photo provided by the domaine here, showing that the yellow point turns an almost red color.
Thanks Iâve always wondered how it would look when overheated as some of mine are a brighter yellow than others.
Canât help with your question, but welcome to WB! Hope you enjoy it here.
Years ago I put a bottle in the oven at 350 degrees for an hour and the white dot stayed white. This was over a decade ago. Never seen a colored one. Yes, my bottle was empty.
Thatâs because the empty sensor triggered upon opening. 
I did the test with a couple of friends recently and the dot seems to work. We all had bottles with different shades of yellow so we were concerned, but when we put a lighter next to the dot it did turn into a very dark orange color.
Do you have pictures of the dots on the wines you got?
First I left my empty bottle outside for an entire 95F day; no change.
Then I baked it in the oven like you did; also no change.
Regardless, the wines arenât very good anyway so Iâm not missing much.
Yes, the two images with a single bottle are the bottles that got us concerned. The image showing the two bottles is one bottle vs. another one heated with a lighter.
That second one looks orange to me. But let me ask you this. You say it arrived at your store. So, I presume itâs a wine store. Did you get a case?
They say their cases have separate temperature detectors you can access on an Android phone. That should clear up any doubts.
No itâs single bottles purchased at separate locations.
They didnât work âas effectivelyâ as the domaine hoped so they dropped them. I donât know what that says about your two winesâŚ
Oh, then itâs an easy call as far as Iâm concerned. Itâs orange.
And considering how hot they say it needs to get, âmore than 45 °C (113 °F) for two hours in order for the ink to react,â I would definitely think itâs seen better days.
